Maps like never before in the Mat-Su

Mat-Su Borough—New, highly detailed, highly accurate mapping data for 3,680 sq/mi of the Matanuska-Susitna Borough’s developed area is changing the way business is done.

The information is the culmination of a $2.1 million dollar project completed in collaboration with nine partners over the last two years at the Borough. This new information is a resource to residents, companies, agencies, and tribal entities for planning, mapping, and in-depth analysis.

Assembly Member Steve Colligan, a GIS expert, supported the project.

“The State of Alaska Digital Elevation Model (DEM) has not until recently started to meet national mapping standards,” Colligan said. “Most of Alaska mapping information is from the 1950s and before the 1964 earthquake.”

“We are pleased with the partnership with federal and state agencies, which has allowed for the Borough to cost share the development of this data. The availability of this data for the recent flooding was invaluable as a management tool, allowing the Borough to be proactive in allocating resources, rather than reactive. I look forward to this information being integrated with other Borough spatial data and being freely available to the public on the Borough website in addition to the global users of Google and Microsoft web map services,” said Colligan.

LiDAR is short for Light Detection and Ranging. It is data collected by sending laser signals from an airplane to the ground. When you drape an image over the elevation data of LiDAR, you can create a three dimensional model.

Before the LiDAR’s release, everyone here in the private sector, design-and-planning field relied on outdated aerials, or had to factor the cost of new imagery into each project budget.

The design firm USKH has already had success with the new data. Based in USKH’s Wasilla office, planner and public involvement consultant Sara Wilson Doyle put the information to work on a recreational master plan.

“Sitting in an office with LiDAR on screen and key trail users in the room lends itself to an analysis that allows fine-tuning and thoughtfulness,” Doyle said.

The project team was able to better analyze slope and new access routes in a short time, with great precision. “The clarity of the new data helped us to identify trail alignments that take advantage of scenic ridges, south-facing sunny slopes, and offer a range of slope conditions from easy to challenging, while providing better drainage for drier trail conditions. We also could see where some user-created trails were already going and incorporate them into new trail alignments,” Doyle said.

Computer analysis also generated point A to point B slope profiles to help the group pinpoint alternative routes for a new road within half an hour of worktime, she said. Otherwise the work would have been left to engineers to gather information from the field.

A number of other map-based products are also available from the Borough including 2-foot contours, hillshades, and building outlines.

This information has greatly improved the Borough’s ability to serve the public. It is used daily to evaluate flood risk to home owners, identify areas of water runoff, conceptualize road design, improve community involvement, promote economic development, and increase public safety, all with an improved level of accuracy.

"With LiDAR, several residents around the Borough are saving thousands of dollars every year on their flood insurance,” said Mark Whisenhunt, Borough Code Compliance Officer.

"Without the use of LiDAR, buckets full of money and hundreds of hours would be wasted trying to do what three clicks of a mouse can accomplish," said Chris Settle, a former Borough Engineering Aide.

The elevation data has also been incorporated into the US Geological Survey National Map, and was submitted to Bing and Google maps. This means that the accuracy of the information has been improved nationwide will directly benefit residents and visitors alike.

Borough Mayor Larry DeVilbiss said he appreciates how geological progression is clearly visible on bare earth maps. “You can see a fault line going through that’s not visible on the ground,” DeVilbiss said. “You can see where towns were built on the delta of gravel from an old Matanuska Riverbed.”

Borough Chief Information Officer Shannon Post said residents will be proud of the dedicated project team and the quality of the information attained.

“In technology, there are pieces of infrastructure necessary to spark innovation. This project lays in place one of those layers of infrastructure, much like a road that opens up access and endless possibilities,” Post said. “I look forward to the creative ideas that it will ignite, and how it will help our community thrive,” Post said.

Image: top left Tools like LiDAR showed why a flash flood brought waist high water into homes outside Wasilla along Marilyn Circle. Notice the depression of a former waterway.

Information about the project can be found on the Borough website (http://www.matsugov.us/it/2011-lidar-imagery-project). There you can find general information about the project, a list of available products, information about ordering data, and additional documentation.